Neuroprotective activity and acetylcholinesterase inhibition of five Amaryllidaceae species: a comparative study.

AIMS: Amaryllidaceae alkaloids exhibit a wide range of physiological effects, of which the acetylcholinesterase (AChE) inhibitory activity is the most relevant. However, scientific evidence related to their neuroprotective effectiveness against glutamate-induced toxicity has been lacking. Thus, the purpose of this study was to conduct a comparative study of the neuroprotective activity and the AChE inhibitory activity of species of Amaryllidaceae. MAIN METHODS: The neuroprotective activity against glutamate-induced toxicity was measured in rat cortical neurons and the Ellman method was employed for the quantification of acetylcholinesterase inhibitory activity of alkaloidal extracts of five species of Amaryllidaceae (Crinum jagus, Crinum bulbispermum, Hippeastrum barbatum, Hippeastrum puniceum and Zephyranthes carinata). The alkaloid Amaryllidaceae patterns based on GC/MS analyses were also investigated. KEY FINDINGS: The results showed that the alkaloidal extract from C. jagus presented a high neuroprotective activity in both pre- and post-treatments against a glutamate excitotoxic stimulus. Furthermore, the alkaloid extracts from C. jagus and Z. carinata revealed an inhibitory activity of AChE from the electric eel with IC50 values of 18.28±0.29 and 17.96±1.22µg/mL, respectively. In addition, 46 alkaloids were detected by GC/MS, and 20 of them were identified based on their mass spectra and retention index. The results suggest that the neuroprotective effects might be associated with lycorine and crinine-type alkaloids, whereas the acetylcholinesterase enzyme inhibitory activity could be related to galanthamine and lycorine-type alkaloids, although not based on synergistic processes. SIGNIFICANCE: In summary, Amaryllidaceae species are sources of alkaloids with potential use for Alzheimer's disease.

INSECTICIDAL ACTIVITY OF PROTEIN EXTRACTS OBTAINED FROM BULBS OF CHILEAN AMARYLLIDACEAE AGAINST TRIALEURODES VAPORARIORUM WESTWOOD AND PSEUDOCOCCUS VIBURNI SIGNORET.

Entomotoxic proteins are produced by plants in defence against insect herbivory. Some carbohydrate-binding proteins exhibit strong insecticidal activity affecting the survival, growth, development and feeding behavior of phytophagous insects. The occurrence of entomotoxic lectins is well documented in the Amaryllidaceae, a plant family spread world-wide. In Chile, this family is represented by numerous species, many of which are also of high ornamental value. Protein extracts were obtained from bulbs of five different species of Chilean Amaryllidaceae. A dose-response assay was carried out with two important pests: the greenhouse whitefly Trialeurodes vaporariorum Westwood and the mealybug Pseudococcus viburni Signoret. The extracts were offered to insects in a liquid artificial diet for three days and the mortality was scored. The Phycella australis Ravenna extract caused the highest insecticidal activity (T. vaporariorum LC50: 7200 µg/mL; P. viburni LC50: 9500 µg/mL). Applied at 1000 µg/mL in the diet the P. australis extract did not repel feeding of these pests. A mannose-binding lectin isolated from the bulbs of P. australis proved to be moderately toxic for these pests (T. vaporariorum LC50: 1127 µg/mL; P. viburni LC50: 2320 µg/mL).

Crinine-type alkaloids from Hippeastrum aulicum and H. calyptratum.

An ongoing search for alkaloids in the Amaryllidaceae species using GC-MS resulted in the identification of two crinine-type alkaloids, aulicine (1) and 3-O-methyl-epimacowine, (2) from the indigenous Brazilian species Hippeastrum aulicum and Hippeastrum calyptratum, respectively. In addition, two alkaloids, 11-oxohaemanthamine (3) and 7-methoxy-O-methyllycorenine (4) were both isolated from H. aulicum. Furthermore, we provide here complete NMR spectroscopic data for the homolycorine analogues nerinine (5) and albomaculine (6). The absolute stereochemistry of the 5,10b-ethano bridge in the crinine variants was determined by circular dichroism and X-ray crystallographic analysis, thus presenting the first direct evidence for the presence of crinine-type alkaloids in the genus Hippeastrum.

Wild Argentinian Amaryllidaceae, a new renewable source of the acetylcholinesterase inhibitor galanthamine and other alkaloids.

The Amaryllidaceae family is well known for its pharmacologically active alkaloids. An important approach to treat Alzheimer's disease involves the inhibition of the enzyme acetylcholinesterase (AChE). Galanthamine, an Amaryllidaceae alkaloid, is an effective, selective, reversible, and competitive AchE inhibitor. This work was aimed at studying the alkaloid composition of four wild Argentinian Amarillydaceae species for the first time, as well as analyzing their inhibitory activity on acetylcholinesterase. Alkaloid content was characterized by means of GC-MS analysis. Chloroform basic extracts from Habranthus jamesonii, Phycella herbertiana, Rhodophiala mendocina and Zephyranthes filifolia collected in the Argentinian Andean region all contained galanthamine, and showed a strong AChE inhibitory activity (IC50 between 1.2 and 2 µg/mL). To our knowledge, no previous reports on alkaloid profiles and AChEIs activity of wild Argentinian Amarillydaceae species have been publisihed. The demand for renewable sources of industrial products like galanthamine and the need to protect plant biodiversity creates an opportunity for Argentinian farmers to produce such crops.

Enhancement of starting up anaerobic digestion of lignocellulosic substrate: fique's bagasse as an example.

In Colombia there are 20,000 ha of fique fields (Furcraea sp., family Agavaceae), that produce around 93,400 tons of fique's bagasse per year. These residuals are disposed into rivers and soil causing pollution. According to physicochemical characteristics, the lignocellulosic residues from fique crops (fique's bagasse) are appropriate carbon source to biogas production. Anaerobic digestion from fique's Bagasse (FB) requires a specialized microbial consortium capable of degrading its high lignocellulosic concentration. In this study, the capacities of seven microbial consortia for biomethane potential (BMP) from FB were evaluated. Inoculum of ruminal liquid achieved high hydrolytic activity (0.068 g COD/g VSS day), whereas pig waste sludge inoculum showed high methanogenic activity (0.146 g COD/g VSS day). Mixtures of these two inoculums (RL+PWS) showed the best yields for biomethane potential (0.3 m(3) CH4/Kg VS ad).

Acetylcholinesterase-inhibiting alkaloids from Zephyranthes concolor.

The bulbs and aerial parts of Zephyranthes concolor (Lindl.) Benth. & Hook. f. (Amaryllidaceae), an endemic species to Mexico, were found to contain the alkaloids chlidanthine, galanthamine, galanthamine N-oxide, lycorine, galwesine, and epinorgalanthamine. Since currently only partial and low resolution (1)H-NMR data for chlidanthine acetate are available, and none for chlidanthine, its 1D and 2D high resolution (1)H- and (13)C-NMR spectra were recorded. Unambiguous assignations were achieved with HMBC, and HSQC experiments, and its structure was corroborated by X-ray diffraction. Minimum energy conformation for structures of chlidanthine, and its positional isomer galanthamine, were calculated by molecular modelling. Galanthamine is a well known acetylcholinesterase inhibitor; therefore, the isolated alkaloids were tested for this activity. Chlidanthine and galanthamine N-oxide inhibited electric eel acetylcholinesterase (2.4 and 2.6 × 10(-5) M, respectively), indicating they are about five times less potent than galanthamine, while galwesine was inactive at 10(-3) M. Inhibitory activity of HIV-1 replication, and cytotoxicity of the isolated alkaloids were evaluated in human MT-4 cells; however, the alkaloids showed poor activity as compared with standard anti-HIV drugs, but most of them were not cytotoxic.

Screening and bioguided fractionation of Amaryllidaceae species with anti-Trichomonas vaginalis activity.

The Amaryllidaceae family is known by its ornamental and medicinal value and has attracted considerable attention due to the content of alkaloids of its species, which showed interesting biological properties. The present study evaluated the anti-Trichomonas vaginalis activity of eighteen extracts (12.5 to 0.19 mg/mL) and six isolated alkaloids (125 to 1.9 µg/mL) from Amaryllidaceae species. The alkaloids diminished the trophozoites viability (from 15 to 40 %). The extracts from Hippeastrum breviflorum demonstrated the highest anti-T. vaginalis activity (viability was 60 % reduced), and a bioguided study was conducted. Six fractions with antiprotozoal activity had lycorine and lycosinine as major components suggesting a synergistic effect, taking into account the higher anti-T. vaginalis activity of extracts when compared to isolated alkaloids. Our results point out the antiprotozoal potential of the Amaryllidaceae species against T. vaginalis. This parasite causes trichomonosis, the most prevalent nonviral sexually transmitted diseases (STD) worldwide and a public health problem that requires new therapeutic alternatives as well bioactive natural products.

Candimine-induced cell death of the amitochondriate parasite Trichomonas vaginalis.

Candimine (1), an alkaloid from the bulbs of Hippeastrum morelianum, was found to be cytotoxic for the amitochondriate parasite Trichomonas vaginalis. Candimine (1) induced cell death with an unprecedented group of effects that failed to fulfill the criteria for apoptosis and apoptosis-like death already reported in trichomonads. Arrest of the parasite cell cycle, and morphologic and ultrastructural alterations, including marked cytoplasmic vacuolization, were induced by 1. The present findings suggest some similarities to paraptotic cell death, described for multicellular organisms. This study contributes to both a better understanding of the biological effects of 1 and T. vaginalis cell biology.

Characterization of calcium oxalate biominerals in some (non-Cactaceae) succulent plant species.

The water-accumulating leaves of crassulacean acid metabolism plants belonging to five different families were investigated for the presence of biominerals by infrared spectroscopic and microscopic analyses. Spectroscopic results revealed that the mineral present in succulent species of Agavaceae, Aizoaceae, and Asphodelaceae was calcium oxalate monohydrate (whewellite, CaC2O4 x H2O). Crystals were predominantly found as raphides or solitary crystals of various morphologies. However, representative Crassulaceae members and a succulent species of Asteraceae did not show the presence of biominerals. Overall, these results suggest no correlation between calcium oxalate generation and crassulacean acid metabolism in succulent plants.

Screening of plants of Amaryllidaceae and related families from Panama as sources of acetylcholinesterase inhibitors.

CONTEXT: This is the first comprehensive study of the acetylcholinesterase (AChE) inhibitory activity of species of the family Amaryllidaceae and 13 related families from Panama. OBJECTIVE: Exploration of the potential sources of AChE inhibitors with radical scavenging activity from Amaryllidaceae and 13 related families from Panama. MATERIALS AND METHODS: The studied plants were screened with anti-acetylcholinesterase bioautographic and DPPH free radical scavenging assays. RESULTS: From the 57 plants studied, eight (14%) showed strong inhibition of AChE, and 29 (51%) plants showed moderate inhibition of AChE. DISCUSSION AND CONCLUSION: Sagittaria lancifolia L. (Alismataceae), Crinum jagus (Thomps.) (Amaryllidaceae), Crinum x amabile Donn (Amaryllidaceae), Crinum zeylanicum (L.) L. (Amaryllidaceae), Crocosmia x crocosmiiflora (Lemoine ex Anonymous) N.E. Br. (Iridaceae), Sisyrinchium tinctorium Kunth (Iridaceae), Agapanthus praecox subsp. orientalis (F.M. Leight.) F.M. Leight. (Liliaceae), and Xyris jupicai Rich. (Xyridaceae) were the most active plants, inhibiting AChE at 100 microg on the TLC bioautographic method for the detection of acetylcholinesterase inhibitors. Out of the eight most active plants, two plants, Crinum zeylanicum (L.) L. and Xyris jupicai Rich., showed antioxidant activity.

Trichomonas vaginalis nucleoside triphosphate diphosphohydrolase and ecto-5'-nucleotidase activities are inhibited by lycorine and candimine.

Drug discovery from plants plays an important role in the pharmaceutical therapy field and the alkaloids lycorine and candimine are candidates for this purpose. Trichomonas vaginalis is a parasite that infects the human urogenital tract and causes trichomonosis, the most prevalent non-viral sexually transmitted disease. Ecto-nucleotidases including nucleoside triphosphate diphosphohydrolase (NTPDase) members, which hydrolyses extracellular ATP (adenosine triphosphate) and ADP (adenosine diphosphate), and ecto-5'-nucleotidase, which hydrolyses AMP (adenosine monophosphate), have been characterized in T. vaginalis. Because purine nucleotides are released from cells under physiological and stress conditions, the goal of this study was to evaluate the effect of lycorine and candimine on T. vaginalis NTPDase and ecto-5'-nculeotidase activities. The alkaloids (50 to 250microM) were tested against both long-term-grown and clinical isolates. Specific enzymatic activities were expressed as nmolPi released/min/mg protein. The effect of both alkaloids at NTPDase A and B expression levels was investigated. When the alkaloids were added directly to the reaction mixture, no effect on ATP, ADP or AMP hydrolysis was observed. NTPDase and ecto-5'-nucleotidase activities were strongly inhibited by candimine and lycorine on 24h-treated parasites. This effect was abolished when 24-treated parasites were innoculated in a culture medium without alkaloid. Transcript levels of NTPDase A or B were not altered by the alkaloids. Considering the cytotoxic and proinflammatory roles of ATP besides the anti-inflammatory effects of adenosine, the regulation of extracellular nucleotide levels could be relevant in increasing susceptibility of T. vaginalis to host immune response in the presence of lycorine and candimine.

Effect of isoquinoline alkaloids from two Hippeastrum species on in vitro acetylcholinesterase activity.

The treatment of neurological disorders and neurodegenerative diseases is related to the levels of acetylcholine (ACh) through the inhibition of acetylcholinesterase (AChE). Galanthamine, an important alkaloid isolated from the Amaryllidaceae family, is approved for the pharmacological treatment of Alzheimer's disease (AD) and acts by inhibiting the acetylcholinesterase (AChE) activity. In the present study, Ellman's method was used to verify the inhibition of AChE activity of some isoquinolines alkaloids such as galanthamine, montanine, hippeastrine and pretazettine. At the concentrations 1mM, 500 microm and 100 microm, galanthamine presented an AChE inhibition higher than 90%. Montanine inhibited, in a dose-dependent manner, more than 50% of the enzyme at 1mM concentration. With the concentrations 500 microm and 100 microm, 30-45% of AChE activity inhibition was detected. The alkaloids hippeastrine and pretazettine presented no significant inhibition of the AChE activity. The results demonstrate that montanine significantly inhibits AChE activity at the tested concentrations, suggesting the necessity of further investigations on this alkaloid use in treating neurological disorders.

Screening for cytotoxic activity of extracts and isolated alkaloids from bulbs of Hippeastrum vittatum.

The dichloromethane and n-butanol extracts obtained from fresh bulbs of Hippeastrum vittatum (Amaryllidaceae), collected in Southern Brazil, were evaluated for their cytotoxic activity in vitro against five human cell lines (HT29 colon adenocarcinoma, H460 non-small cell lung carcinoma, RXF393 renal cell carcinoma, MCF7 breast cancer, and OVCAR3 epithelial ovarian cancer), using the sulphorhodamine B assay. Both extracts showed potential antiproliferative activity. From CH(2)Cl(2) fraction, three alkaloids were isolated: lycorine, vittatine and montanine. The two last compounds were submitted to the antiproliferative assay and the highest level of cytotoxicity was found for the alkaloid montanine.

Anxiolytic-, antidepressant- and anticonvulsant-like effects of the alkaloid montanine isolated from Hippeastrum vittatum.

Compounds isolated from different members of the Amaryllidaceae family are becoming relevant options for the treatment of neurological disorders and neurodegenerative diseases. In particular, species of the Hippeastrum genus are important source of alkaloids with a wide profile of putative therapeutical applications. Here, we report on the behavioral and pharmaco-toxicological characterization of montanine, an isoquinoline alkaloid isolated from Hippeastrum vittatum, an ornamental plant found throughout the world. In mice, montanine showed a LD(50) of 64.7 mg/kg and 67.6 mg/kg for male and female, respectively. When given i.p., montanine dose-dependently decreased sodium pentobarbital-induced sleep, protected against pentylenetetrazole-provoked convulsions, increased the number of entries and the time spent in the open arms of an elevated plus maze and augmented the time spent struggling during a forced swimming test. When given immediately after inhibitory avoidance training, montanine did not affect avoidance memory retention in rats. Our results suggest that montanine, as other alkaloids isolated from Amaryllidaceae species, has psychopharmacological activities including anxiolytic, antidepressive and anticonvulsive effects.

In vitro cytotoxicity of some natural and semi-synthetic isocoumarins from Paepalanthus bromelioides.

Numerous natural compounds have a potential for therapeutic applications, but may have to be chemically modified to alter toxic side effects. We investigated structural parameters that could affect the cytotoxicity of isocoumarins similar to 9,10-dihydroxy-5,7-dimethoxy-1H-naphtho(2,3c)pyran-1-one (paepalantine 1). Paepalantine 1 has antimicrobial activity, as well as significant in vitro cytotoxic effects in the McCoy cell line. Two other natural and two semi-synthetic isocoumarins with similar structures obtained from the capitula of Paepalanthus bromelioides were tested on the same cell line by the neutral red assay. Substitution of the 9 and/or 10-OH group made these compounds less cytotoxic.

Chemical, physical and morphometric properties of Peruvian carrot (Arracacia xanthorrhiza B.) starch.

Starch was isolated from Peruvian carrot (PC)--or arracacha--(Arraccacia xanthorrhiza B.) roots. Its chemical, physical, physicochemical and granular structural properties were compared to those of commercial cassava starch. Scanning electron microscopy revealed a granular size for PC starch ranging between 4 and 26 microns in diameter, with spherical and truncated-egg shapes. PC and cassava starches were similar regarding gross chemical composition and basic physical characteristics but differed in pasting properties, with PC starch showing lower breakdown and consistency indices. The two starches also showed different water absorption and solubility patterns.

Chemical, physical and morphometric properties of peruvian carrot (Arracacia xanthorrhiza B.) starch

Starch was isolated from Peruvian carrot (PC) -or arracacha- (Arracacia xanthorhiza B.) roots. Its chemical, physical, physicochemical and granular structural properties were compared to those of commercial cassava starch. Scanning electron microscopy revealed a granular size for PC starch ranging between 4 and 26 mum in diameter, with spherical and truncated-egg shapes. PC and cassava starches were similar regarding gross chemical composition and basic physical characteristics but differed in pasting properties, with PC starch showing lower breakdown and consistency indices. The two starches also showed different water absorpption and solubility patterns.

Evaluación de la yuca como materia prima no convencional para la industria alimentaria / Cassava evaluation as no convencional resourse for food industry

Se describe brevemente la composición química promedio de la yuca cultivada en diversas regiones de México, siendo el componenete más importante el almidón, que permite el aprovechamiento de un recurso natural como prima no convencional para la industria alimentaria en la elaboración de productos tales como, dextrinas, jarabes glucosados y fructosados. Como ingrediente, el almidón de yuca se utiliza en la producción de alimentos para bebés, embutidos, salsas y mayonesas. Los almidones modificados se emplean principalmente en panadería en la producción de pies, rellenos y producción congelados, ya que por sus características físico-químicas imparten estabilidad y proporcionan un producto final que se mantiene fresco y de excelente textura